Marlo Thomas grew up surrounded by comedy legends. Milton Berle did magic tricks at her birthday parties (and was heckled by the kids). George Burns, Sid Caesar, Don Rickles, Bob Newhart, and all the others all played cards with her dad, Danny Thomas, and were frequent guests. The Thomas’s dinner table was a stage, and the quickest way out of trouble for Marlo and her siblings was to make her dad laugh.

The interviews are all centered around the comedians’ memories of growing up and when they first realized they were funny, so even though both Conan O’Brien and Jay Leno are interviewed, those looking for more fodder about “The Tonight Show” brouhaha will need to look elsewhere.

Thomas’s questions aren’t what you’d call hard-hitting – they range in speed from softball to Wiffle ball. But the fact that she’s such a generous, appreciative audience – her most frequent quotes are “That is so great,” and “You are so funny” – means that she’s able to talk to even press-shy comedians like Jerry Seinfeld, her leadoff interview.

“One of the things that drew me to comedy was it’s a simple world. It doesn’t require the interpretation of any critic to tell you whether something is good or not good. If the audience is laughing, the guy’s good,” Seinfeld says, before riffing on the latent donkey hostility inherent in children’s birthday parties.High school and the family dinner table, it turns out, are remarkably effective comedy incubators.

As O’Brien puts it, when people ask why he still makes fun of himself, his comedy defenses were honed when he was a skinny, freckled teen with orange hair who wasn’t good at sports. They’re so ingrained now, he says, “I could be made dictator of the world tomorrow, and I would still make fun of myself.”

Thomas had a rarified upbringing – when she and her friends played tricks on Halloween, it was Edward G. Robinson’s windows they were soaping. George Lopez’s comedy hails from the other end of the economic spectrum. “For my family, shopping was like ‘The Price is Right,’ ” he jokes before reminiscing about using the sun to blow up their basketball, because they couldn’t afford a pump.

Thomas also covers her days as co-founder, with Gloria Steinem, of the Ms. Foundation, and her roles on Broadway and as a TV producer. That last leads to the only truly uncomfortable moment in “Growing Up Laughing”: When Thomas talks about remaking “It’s a Wonderful Life” against Frank Capra’s express wishes.

“She’s an interesting woman,” said costar Orson Welles on “The Tonight Show” after that project. “She’s a cross between St. Theresa of the Flowers and Attila the Hun.”

For those who remember Thomas mostly from her fundraising work for St. Jude’s Children’s Hospital or her classic children’s album, “Free to Be ... You and Me,” she offers proof of her own comedy chops. There are pages of jokes from everyone from George Carlin (along with an unrecognizable photo of him on “That Girl”) to Roseanne Barr, but Thomas gets the biggest laugh. The reprint of her interviewing comedy writer Elaine May for Interview magazine made me laugh so hard my husband came into the room, wondering if I was OK. I believe I was at the point when May is saying, “And it’s always fun to take a weak, vulnerable person and slam them up against the wall.”

By interspersing the interviews with her own memories of her father, a stand-up comedian who starred in “Make Room for Daddy,” Thomas helps place him in the tradition of American stand-up, as well as show how the business has evolved since the days when he, Caesar, and the others would sit in their dressing rooms in their tuxedo jackets and shorts, since they didn’t want to insult the audience with wrinkles on their trousers.

Nor is she the only working comedian today who grew up with professionally funny parents. Ben Stiller, who’s interviewed with his father, Jerry, grew up with not one, but two veteran comics in the family. (His mother is Anne Meara.) When his parents were home, he and his sister would put on shows for them – rather like Thomas and her siblings.

“Children everywhere imitate the grown-ups in their lives,” Thomas writes. “Showbiz kids just have more material to work with.”